Elliptical Locus of a Circle Tangent to Two Given Circles
2013-06-10 08:09
This GeoGebra applet demonstrates the locus of the center of a moving circle internally tangent to a larger circle and externally tangent to a smaller one. Adjusting the radii and positions reveals that the center's path forms an ellipse. It combines geometric construction and locus tracing to illustrate the ellipse's geometric definition, ideal for teaching conic sections.
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Conic Sections | GeoGebra Book
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